Colored contact lens, manufacturing method of colored contact lens, and iris recognition system

ABSTRACT

Provided is a colored contact lens having: a lens; and a colored region formed in the lens, at least a part of the colored region is arranged at a position overlapping an iris of a wearer when the colored contact lens is worn, and the colored region has infrared transparency.

CROSS-REFERENCE TO RELATED APPLICATIONS

The present application is a continuation application of U.S. patentapplication Ser. No. 16/646,868 filed on Mar. 12, 2020, which is aNational Stage Entry of international application PCT/JP2018/034288,filed on Sep. 14, 2018, which claims the benefit of priority fromJapanese Patent Application 2017-224343 filed on Nov. 22, 2017, thedisclosures of all of which are incorporated in their entirety byreference herein.

TECHNICAL FIELD

The present invention relates to a colored contact lens, a manufacturingmethod of the colored contact lens, and an iris recognition system.

BACKGROUND ART

Patent Literature 1 discloses a colored contact lens having a coloredregion. When the colored contact lens is worn, an iris of the wearer iscovered with a colored region. Thus, the appearance of the iris changes.

CITATION LIST Patent Literature

PTL 1: International Publication No. 2014/125742

SUMMARY OF INVENTION Technical Problem

When a colored contact lens as disclosed in Patent Literature 1 is worn,the appearance of the pattern of an iris changes to a pattern differentfrom the actual iris of the wearer. Thus, when iris recognition isperformed on a wearer of a colored contact lens, recognition accuracymay be degraded.

The present invention has been made in view of the problem describedabove and intends to provide a colored contact lens and a manufacturingmethod of the colored contact lens and an iris recognition system thatcan reduce influence on accuracy of iris recognition.

Solution to Problem

According to one example aspect of the present invention, provided is acolored contact lens including: a lens; and a colored region formed inthe lens, at least a part of the colored region is arranged at aposition overlapping an iris of a wearer when the colored contact lensis worn, and the colored region has infrared transparency.

According to another example aspect of the present invention, providedis a manufacturing method of a colored contact lens, the manufacturingmethod including: forming a lens; and forming a colored region in thelens, at least a part of the colored region is arranged at a positionoverlapping an iris of a wearer when the colored contact lens is worn,and the colored region has infrared transparency.

According to yet another example aspect of the present invention,provided is an iris recognition system including: an infrared imageacquisition unit that captures an iris of a recognition subject wearinga colored contact lens having a colored region by using an infrared rayhaving a wavelength that transmits the colored region; a visible lightimage acquisition unit that captures the iris by using a visible light;a determination unit that determines whether or not the recognitionsubject is wearing the colored contact lens; and a comparison unit thatperforms comparison on the iris, when the determination unit determinesthat the recognition subject is wearing the colored contact lens, therecognition unit performs comparison by using an image acquired by aninfrared ray, and when the determination unit determines that therecognition subject is not wearing the colored contact lens, therecognition unit performs comparison by using an image acquired by avisible light or an infrared ray.

Advantageous Effects of Invention

According to the present invention, a colored contact lens and amanufacturing method of the colored contact lens and an iris recognitionsystem that can reduce influence on accuracy of iris recognition can beprovided.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 is a plan view of a colored contact lens according to a firstexample embodiment.

FIG. 2 is a sectional view of the colored contact lens according to thefirst example embodiment.

FIG. 3 is a schematic diagram illustrating a manufacturing method of thecolored contact lens according to the first example embodiment.

FIG. 4 is a graph illustrating an example of wavelength dependency ofthe transmittance of a colored region according to the first exampleembodiment.

FIG. 5 is a schematic diagram of an image of an eye wearing a coloredcontact lens captured by a visible light camera.

FIG. 6 is a schematic diagram of an image of an eye wearing a coloredcontact lens captured by an infrared camera.

FIG. 7 is a block diagram illustrating a hardware configuration exampleof an iris recognition system according to the first example embodiment.

FIG. 8 is a function block diagram of the iris recognition systemaccording to the first example embodiment.

FIG. 9 is a flowchart illustrating an iris recognition process accordingto the first example embodiment.

FIG. 10 is a function block diagram of an iris recognition systemaccording to a second example embodiment.

FIG. 11 is a flowchart illustrating an iris recognition processaccording to the second example embodiment.

FIG. 12 is a plan view of a contact lens according to a third exampleembodiment.

FIG. 13 is a flowchart illustrating a manufacturing method of a contactlens according to a fourth example embodiment.

DESCRIPTION OF EMBODIMENTS

Exemplary example embodiments of the present invention will be describedbelow with reference to the drawings. Throughout the drawings, similarcomponents or corresponding components are labeled with the samereferences, and the description thereof may be omitted or simplified.

First Example Embodiment

FIG. 1 is a plan view of a colored contact lens 10 according to thepresent example embodiment, and FIG. 2 is a sectional view taken along aline A-A of the colored contact lens 10 according to the present exampleembodiment. The colored contact lens 10 has a lens 100 and a coloredregion 110 formed in the lens 100. As illustrated in FIG. 1 and FIG. 2,the lens 100 has a meniscus shape in which one face is a convex and theother face is a concave. The colored region 110 has an annular shape ina planar view. The colored region 110 is arranged at a position where atleast a part thereof overlaps an iris of a wearer when the coloredcontact lens 10 is worn. Thereby, a decoration effect of the iris isobtained. The colored region 110 is often arranged at a positioncovering the outer circumference of the wearer's iris in order to obtainan effect of causing an iris to look larger.

Further, a transparent portion 120 is arranged at a positioncorresponding to a pupil inside the colored region 110. This can preventthe colored region 110 from blocking the vision when the colored contactlens 10 is worn. Note that the colored contact lens may be referred toas a color contact lens, a circle contact lens, or a cosmetic contactlens.

Note that, while the colored region 110 has an annular shape forsimplified illustration in FIG. 1, the shape is not limited thereto. Forexample, various shapes such as one whose pattern of the colored region110 has a radial shape close to a pattern of an actual iris, one whosecolor of the colored region 110 has gradation with multiple dotpatterns, or the like may be employed.

FIG. 3 is a schematic diagram illustrating a manufacturing method of thecolored contact lens 10 according to the present example embodiment.Each of step (a) to step (d) in FIG. 3 illustrates a sectional view ofthe colored contact lens 10 and a mold 210 used for molding it. WhileFIG. 3 illustrates a so-called sandwich scheme as one example of amanufacturing method of the colored contact lens 10, other schemes maybe used. One example of the manufacturing method of the colored contactlens 10 will be described below along the order of steps in FIG. 3.

In step (a), a resin 220 is supplied to the mold 210. The resin 220 ismolded as a lens 100 a having a meniscus shape along the concave of themold 210. A spin cast method, a cast mold method, or the like may beused for the molding of the resin 220. The spin cast method is a methodto perform molding by utilizing centrifugal force generated by rotatingthe mold 210. The cast mold method is a scheme to perform molding byfitting a convex mold, which is different from the mold 210, to theconcave of the mold 210.

In step (b), a coloring material 230 is formed on the lens 100 a. Thecoloring material 230 forms the colored region 110. Then, in step (c),the resin 220 is again supplied over the lens 100 a so as to cover thecoloring material 230, and the molding of the resin 220 is performed.This results in a state where the colored region 110 formed of thecoloring material 230 is interposed inside the lens 100. After the resinforming the lens 100 is solidified, in step (d), the colored contactlens 10 is released from the mold 210.

The colored contact lens 10 may be a soft contact lens or a hard contactlens. For example, when the colored contact lens 10 is a soft contactlens, the material of the resin 220 may be one commonly used, such ashydroxyethyl methacrylate, silicone hydrogel, or the like.

The nature of the colored region 110 will be described. A materialhaving infrared transparency is used for the coloring material 230.Thereby, the colored region 110 has infrared transparency. Further, amaterial having absorbability or reflectivity to a visible light is usedfor the coloring material 230. Thereby, the colored region 110 is opaqueto a visible light, and a decoration effect such as an effect to causean iris to look larger, an effect to change the color of an iris, or thelike can be obtained. For example, such the coloring material 230 iscommercially available as infrared transparent ink and may be used for afilter or the like of a transceiver unit of an infrared communicationdevice.

Here, a visible light refers to a light whose wavelength is longer thanor equal to 400 nm and shorter than or equal to 750 nm. Most persons areable to recognize a light of such a range by their vision. Thus, amaterial having absorbability or reflectivity to a light having awavelength of such a range may be suitably used as a coloring material.An infrared ray refers to a light whose wavelength is longer than 750nm. The colored region 110 has infrared transparency and thus transmitsa light whose wavelength is longer than 750 nm. Note that, in thepresent specification, mere reference to “light” or the like withoutlimitation of wavelength is not limited to mean a visible light but mayinclude an electromagnetic wave of any wavelength, such as a visiblelight and an infrared ray.

FIG. 4 is a graph illustrating an example of wavelength dependency ofthe transmittance of the colored region 110 according to the presentexample embodiment. The horizontal axis of FIG. 4 illustrates thewavelength of a light entering the colored region 110, and the verticalaxis illustrates the transparency of the light corresponding to thewavelength. As understood from FIG. 4, the transmittance of the coloredregion 110 is low for the visible light whose wavelength is longer thanor equal to 400 nm and shorter than or equal to 750 nm. Thus, thecolored region 110 is observed as a region colored in black or the likeby a naked eye or a visible light camera. Further, the transmittance ofthe colored region 110 is high for an infrared ray whose wavelength islonger than 750 nm. Thus, the colored region 110 is observed as a regionclose to be transparent by the infrared camera.

As discussed above, in the colored contact lens 10 of the presentexample embodiment, the colored region 110 has frequency dependency ontransmittance as described above, and thereby the colored region 110 hasdifferent appearance between a visible light and an infrared ray,respectively. FIG. 5 is a schematic diagram of an image of an eye 300wearing the colored contact lens 10, which has been captured by avisible light camera. As illustrated in FIG. 5, an end 100 b of the lens100, the colored region 110, and the transparent portion 120 can bedetermined from the image captured by the visible light camera. Further,since the transparent portion 120 is transparent to a visible light, apupil 310 inside the colored contact lens 10 can be externallydetermined. Since the iris of the wearer is covered and hidden by thecolored region 110, however, the pattern of the iris of the wearer isunable to be determined by the visible light.

FIG. 6 is a schematic diagram of an image of the eye 300 wearing thecolored contact lens 10, which has been captured by an infrared camera.As illustrated in FIG. 6, since the colored region 110 is transparent inthe image captured by the infrared camera, a pattern 330 of an iris 320of the wearer inside the colored contact lens 10 is able to bedetermined.

When a colored contact lens is worn, an iris is covered by a coloredregion. Thus, when iris recognition is performed on a wearer of acolored contact lens, recognition accuracy may be deteriorated. Whilethe pattern near the outer circumference of an iris that is less likelyto be affected by contraction of a pupil is one of the important factorsin iris authentication, in a colored contact lens, a colored region isoften arranged near the outer circumference of an iris in order toobtain an effect to cause the iris to look larger. In such a case,influence of recognition accuracy deterioration is likely to occur.

In contrast, in the colored contact lens 10 of the present exampleembodiment, at least a part of the colored region 110 has infraredtransparency. Thus, even when an iris of a wearer is covered by thecolored region 110, it is possible to determine the pattern of the irisof the wearer by capturing the eye by using an infrared camera.Therefore, according to the present example embodiment, the coloredcontact lens 10 that can reduce influence on accuracy of irisrecognition is provided.

In such a way, the colored contact lens 10 of the present exampleembodiment can perform iris recognition even when worn. Thus, forexample, even when iris recognition is employed for identityverification such as identity verification at the time of login to asmartphone, identity verification at the time of entry to or exit from afacility, it is not necessary to put off a contact lens at the time ofauthentication, which improves convenience.

Note that the expression “having infrared transparency” is not limitedto refer to a state where an infrared ray completely transmits. Anystate may be included as long as there may be transparency to the degreeat which the pattern of an iris of a wearer can be determined bycapturing an eye by using an infrared camera. For example, when thetransmittance of the colored region 110 to an infrared ray whosewavelength is longer than 750 nm and shorter than 1000 nm is larger thanthe transmittance of the colored region 110 to a visible light whosewavelength is longer than or equal to 400 nm and shorter than or equalto 750 nm, it can be said that there is infrared transparency.Similarly, the expression “having absorbability or reflectivity” is notlimited to refer to a state where no light transmits.

In the present example embodiment, the colored region 110 may be formedof a coloring material 230 having infrared transparency. At this time,the coloring material 230 may be formed to be interposed inside the lens100. In this manufacturing method, the coloring material 230 is notcontained in the surface of the lens but contained inside the lens.Since the coloring material 230 does not come into contact with aneyeball, an eyelid, or the like when the colored contact lens 10 isworn, the colored contact lens 10 of the present example embodiment hasthe structure that is less likely to affect a living body.

Note that it is not essential that the entire colored region 110 haveinfrared transparency as long as at least a part of a portion coveringan iris of the colored region 110 has infrared transparency. Forexample, while a pattern extending up to the outside of an iris of awearer may be provided in the colored contact lens 10, the portionoutside an iris of a wearer may not have infrared transparency.

Next, a configuration example of an iris recognition system thatperforms iris recognition on a subject wearing the colored contact lens10 according to the present example embodiment will be described.

FIG. 7 is a block diagram illustrating a hardware configuration exampleof an iris recognition system 40 that performs iris recognitionaccording to the present example embodiment. The iris recognition system40 may be a computer or an information communication terminal such as amobile phone, a smartphone, a tablet personal computer (PC), a laptopPC, a desktop PC, or the like, for example. The iris recognition system40 has a function of iris recognition that is a type of biometricsrecognition. The iris recognition system 40 captures an iris of a userthat is a recognition subject and performs iris recognition by comparingthe captured iris image with a registered iris image. A pattern of aniris is unique and permanent for a person. It is therefore possible tocheck whether or not the same person is identified by comparing thepattern of the iris acquired at the time of recognition with thepre-registered iris image. While it is assumed that the iris recognitionsystem 40 is mounted on a smartphone as an example and iris recognitionis performed for identity verification at the time of login by the userin the following description, the invention is not limited thereto.

The iris recognition system 40 has a central processing unit (CPU) 401,a random access memory (RAM) 402, a read only memory (ROM) 403, and aflash memory 404 in order to implement functions of a computer thatperforms calculation and storage. Further, the iris recognition system40 has a communication interface (I/F) 405, a display device 406, aninput device 407, a visible light irradiation device 408, a visiblelight camera 409, an infrared irradiation device 410, and an infraredcamera 411. The CPU 401, the RAM 402, the ROM 403, the flash memory 404,the communication I/F 405, the display device 406, the input device 407,the visible light irradiation device 408, the visible light camera 409,the infrared irradiation device 410, and the infrared camera 411 areconnected to each other via a bus 412. Note that the display device 406,the input device 407, the visible light irradiation device 408, thevisible light camera 409, the infrared irradiation device 410, and theinfrared camera 411 may be connected to the bus 412 via a drive device(not illustrated) used for driving these devices.

While respective components forming the iris recognition system 40 areillustrated in FIG. 7 as an integrated device, some of the functionsthereof may be formed by an externally attached device. For example, thevisible light irradiation device 408, the visible light camera 409, theinfrared irradiation device 410, or the infrared camera 411 may beexternally attached devices that are separate from a part forming thefunction of a computer including the CPU 401 or the like.

The CPU 401 also has a function of performing a predetermined operationin accordance with a program stored in the ROM 403, the flash memory404, or the like and controlling each component of the iris recognitionsystem 40. The RAM 402 is formed of a volatile storage medium andprovides a temporary memory field required for the operation of the CPU401. The ROM 403 is formed of a nonvolatile storage medium and storesnecessary information such as a program used in the operation of theiris recognition system 40. The flash memory 404 is a storage devicethat is formed of a nonvolatile storage medium and stores an imagecaptured by the infrared camera 411 or the like, an image of arecognition subject, feature amount data, or the like.

The communication I/F 405 is a communication interface based on aspecification such as Wi-Fi (registered trademark), 4G, or the like,which is a module for communicating with other devices. The displaydevice 406 is a liquid crystal display, an organic light emitting diode(OLED) display, or the like and is used for displaying a moving image, astatic image, a text, or the like. The input device 407 is a button, atouchscreen, or the like and is used by a user to operate the irisrecognition system 40. The display device 406 and the input device 407may be integrally formed as a touchscreen.

The visible light irradiation device 408 and the visible light camera409 are provided on a display face of the display device 406 or thelike, for example. The visible light irradiation device 408 is used as alight source for capturing by the visible light camera 409, for example.The visible light camera 409 can capture a landscape, a face or an eyeof a user, or the like with a visible light to acquire an image. Adigital camera with a Complementary Metal Oxide Semiconductor (CMOS)image sensor, a Charge Coupled Device (CCD) image sensor, or the likemay be used for the visible light camera 409 in terms of suitable imageprocessing after capturing.

The infrared irradiation device 410 is a light emitting element such asan infrared LED that emits an infrared light. A digital camera with aCMOS image sensor, a CCD image sensor, or the like having a lightreceiving element configured to have a sensitivity to an infrared raymay be used for the infrared camera 411. By irradiating a user's eyewith an infrared ray from the infrared irradiation device 410 andcapturing an infrared ray reflected at an iris by using the infraredcamera 411, it is possible to capture an iris image used for irisrecognition. By using an infrared ray to acquire an iris image, it ispossible to obtain an image having a high contrast regardless of thecolor of the iris and reduce influence of reflection at a cornea. Notethat the infrared camera 411 can be omitted when the visible lightcamera 409 can acquire an image with an infrared ray in addition to avisible light. The wavelength of an infrared ray irradiated from theinfrared irradiation device 410 may be, for example, in a range longerthan 750 nm and shorter than 1000 nm.

Note that the hardware configuration illustrated in FIG. 7 is an exampleand a device other than the above may be added or some of the devicesmay not be provided. Further, some of the devices may be replaced withanother device having the same function. Furthermore, a part of thefunction may be provided by another device via a network, or thefunction forming the present example embodiment may be distributed to aplurality of devices for implementation. For example, the flash memory404 may be replaced with a Hard Disk Drive (HDD) or may be replaced withcloud storage.

FIG. 8 is a function block diagram of the iris recognition system 40according to the present example embodiment. The iris recognition system40 has an infrared irradiation unit 421, an infrared image acquisitionunit 422, a feature amount calculation unit 423, a comparison unit 424,and a storage unit 425.

The CPU 401 implements the function of the infrared irradiation unit 421that irradiates an eye of a recognition subject with an infrared ray bycontrolling the infrared irradiation device 410. The CPU 401 implementsthe function of the infrared image acquisition unit 422 that acquires aninfrared image of an eye of a recognition subject by controlling theinfrared camera 411. The CPU 401 implements the function of the featureamount calculation unit 423 and the comparison unit 424 by loading aprogram stored in the ROM 403 or the like to the RAM 402 and executingthe program. The process performed by each of these units will bedescribed later. The storage unit 425 stores data such as an iris imageacquired by the infrared image acquisition unit 422, an iris imageregistered in advance, and a feature amount calculated from these irisimages, or the like. The CPU 401 implements the function of the storageunit 425 by controlling the flash memory 404.

FIG. 9 is a flowchart illustrating the outline of an iris recognitionprocess performed by the iris recognition system 40 according to thepresent example embodiment. In step S101, the infrared irradiation unit421 irradiates a region including an eye of a recognition subject withan infrared ray. The infrared image acquisition unit 422 acquires aninfrared image based on a reflected light of the irradiated infraredray. The acquired infrared image is stored in the storage unit 425.Typically, such an infrared image is a grayscale image.

In step S102, the feature amount calculation unit 423 calculates afeature amount by using the pattern of the iris included in the infraredimage. The calculated feature amount is stored in the storage unit 425.

In step S103, the comparison unit 424 compares the feature amountacquired in step S102 with a feature amount of the iris of therecognition subject registered in advance in the storage unit 425. If itis determined that the comparison corresponds to the iris of the sameperson, the iris recognition system 40 determines that identityverification is successful and performs a process such as login.

As described above, according to the iris recognition system 40according to the present example embodiment, it is possible to acquirean infrared image of an iris to perform iris recognition. It istherefore possible to perform iris recognition on a subject wearing thecolored contact lens 10 having infrared transparency.

The wavelength of a light used for acquiring an image of an iris will bedescribed. While the wavelength used for acquisition of an image of aniris described above may be appropriately selected as long as it iswithin a range of an infrared region, it is desirable to set thewavelength taking the accuracy of iris recognition into consideration asdescribed below.

In the iris recognition, the score indicating a matching degree ofcomparison at a wavelength around 800 nm is likely to be high, whichenables accurate recognition. Since an excessively long wavelengthreduces the score and reduces the accuracy of iris recognition, it isdesirable that the wavelength of a light used for acquiring an image beshorter than 1000 nm. On the other hand, since there is an advantage ina use of an infrared image that iris authentication is enabled with thecolored contact lens 10 being worn as described above, it is desirablethat that the wavelength of a light used for acquiring an image of aniris be longer than 750 nm. Given these conditions, it is desirable thatthe wavelength of a light used for acquiring an image of an iris bewithin a range longer than 750 nm and shorter than 1000 nm. Accordingly,it is desirable that the colored region 110 of the colored contact lens10 also have transparency to a light whose wavelength is longer than 750nm and shorter than 1000 nm.

Second Example Embodiment

As a second example embodiment of the present invention, an irisrecognition system 50 having a function of determining whether or notthe colored contact lens 10 is worn will be described.

FIG. 10 is a function block diagram of the iris recognition system 50according to the present example embodiment. The iris recognition system50 further has a visible light irradiation unit 426, a visible lightimage acquisition unit 427, and a determination unit 428 in addition tothe configuration of the iris recognition system 40 of the first exampleembodiment.

The CPU 401 implements the function of the visible light irradiationunit 426 that irradiates an eye of a recognition subject with a visiblelight by controlling the visible light irradiation device 408. The CPU401 implements the function of the visible light image acquisition unit427 that acquires a visible light image of an eye of a recognitionsubject by controlling the visible light camera 409. The CPU 401implements the function of the determination unit 428 by loading aprogram stored in the ROM 403 or the like to the RAM 402 and executingthe program. The function of the determination unit 428 will bedescribed later.

FIG. 11 is a flowchart illustrating the outline of an iris recognitionprocess performed by the iris recognition system 50 according to thepresent example embodiment.

In step S201, a visible light image and an infrared image are acquired.These images are used in determination in subsequent step S202 as towhether or not the colored contact lens 10 is worn. The infrared imageof the eye of the recognition subject is acquired by the same process asstep S101 of FIG. 9. Further, a visible light image of the eye of therecognition subject is acquired by the visible light irradiation unit426 and the visible light image acquisition unit 427. The visible lightirradiation unit 426 irradiates a region including the eye of therecognition subject with a visible light. The visible light imageacquisition unit 427 acquires a visible light image based on a reflectedlight of the irradiated visible light. The acquired visible light imageis stored in the storage unit 425.

In step S202, the determination unit 428 uses the visible light imageand the infrared image acquired in step S201 to determine whether or notthe recognition subject is wearing the colored contact lens 10. Thisdetermination may be performed by comparing the visible light image andthe infrared image and based on whether or not the difference for aportion corresponding to an iris exceeds a threshold, for example. Asseen from FIG. 5 and FIG. 6, this is because the pattern of a portioncorresponding to the colored region 110 is different between a visiblelight image and an infrared image. Alternatively, a determiner which hasperformed learning in advance through machine learning may be used asthe determination unit 428. A visible light image and an infrared imageobtained when the colored contact lens 10 is worn and a visible lightimage and an infrared image obtained when the colored contact lens 10 isnot worn may be used for teaching data for learning.

If it is determined that the recognition subject is wearing the coloredcontact lens 10 in step S202 (step S202, YES), the process proceeds tostep S203. If it is determined that the recognition subject is notwearing the colored contact lens 10 in step S202 (step S202, NO), theprocess proceeds to step S204.

In step S203, the feature amount calculation unit 423 calculates afeature amount by using the pattern of the iris included in the infraredimage. The calculated feature amount is stored in the storage unit 425.

In step S204, the feature amount calculation unit 423 calculates afeature amount by using the pattern of the iris included in the visiblelight image. The calculated feature amount is stored in the storage unit425. Since the subsequent process is the same as that of the irisrecognition system 40 of the first example embodiment, the descriptionthereof will be omitted.

Note that it is not essential to calculate a feature amount by using avisible light image in the process of step S204, and a feature amountmay be calculated by using an infrared image also in step S204. That is,in the process of step S204, a feature amount may be calculated by usingany of an infrared image or a visible light image. For example, theimage used for calculation of a feature amount may be changed inaccordance with a situation, such as an image in which the pattern of aniris is clearly displayed may be selected for use in the feature amountcalculation process.

As described above, the iris recognition system 50 of the presentexample embodiment can determine whether or not the colored contact lens10 having a colored region with infrared transparency is worn. When thecolored contact lens 10 is worn, the iris recognition system 50 canperform iris recognition by using an infrared image and reduce influenceof the colored contact lens 10 on recognition accuracy. Further, whenthe colored contact lens 10 is not worn, the iris recognition system 50can use a visible light image for iris recognition, for example. This isbecause, in such a case, no restriction is necessary as to which imageto use for iris recognition. Therefore, flexibility of processing isimproved.

The colored contact lens described in the above example embodiments mayalso be configured as a third example embodiment below.

Third Example Embodiment

FIG. 12 is a plan view of a colored contact lens 60 according to thepresent example embodiment. The colored contact lens 60 has a lens 600and a colored region 610 formed in the lens 600. Here, at least a partof the colored region 610 is arranged at a position overlapping an irisof a wearer when the colored contact lens 60 is worn. Further, thecolored region 610 has infrared transparency.

According to the present example embodiment, a colored contact lens thatcan reduce influence on accuracy of iris recognition can be provided.

A manufacturing method of the colored contact lens described in theabove example embodiments may also be configured as a fourth exampleembodiment below.

Fourth Example Embodiment

FIG. 13 is a flowchart illustrating a manufacturing method of a coloredcontact lens according to the fourth example embodiment. In step S301, alens is formed. In step S302, a colored region is formed in the lens.Here, at least a part of the colored region is arranged at a positionoverlapping an iris of a wearer when the colored contact lens is worn.Further, the colored region has infrared transparency.

According to the present example embodiment, a manufacturing method of acolored contact lens that can reduce influence on accuracy of irisrecognition can be provided.

Modified Example Embodiment

The present invention is not limited to the example embodimentsdescribed above and can be appropriately changed within a scope notdeparting from the spirit of the present invention.

The iris recognition systems 40 and 50 of the example embodimentsdescribed above may be used not only for authentication at the time oflogin illustrated as an example but also for various identityverification. For example, the iris recognition systems of the exampleembodiments described above may be applied to identity verification forentry into or departure from a country at an airport, a seaport, or anational border, identity verification at an administrativeorganization, identity verification for entry to or exit from a factoryor an office, identity verification at the time of entry to an eventsite, or the like.

In each of the example embodiments described above, acquisition of animage used for iris recognition may be performed on one of the eyes ofan authentication subject or may be performed on both of the eyes. Thereare advantages of improvement of processing speed or reduction ofstorage capacity when an image of only one of the eyes is acquired, andthere is an advantage of improvement of authentication accuracy whenimages of both of the eyes are acquired.

The scope of each example embodiment also includes a processing methodof storing, in a storage medium, a program that causes the configurationof the example embodiment to operate to implement the function of theexample embodiment described above, reading out as a code the programstored in the storage medium, and executing the code in a computer. Thatis, a computer readable storage medium is also included in the scope ofeach example embodiment. Further, not only the storage medium in whichthe program described above is stored but also the program itself isincluded in each example embodiment. Further, one or more componentsincluded in the example embodiments described above may be a circuitsuch as an Application Specific Integrated Circuit (ASIC), a FieldProgrammable Gate Array (FPGA), or the like configured to implement thefunction of each component.

As the storage medium, for example, a floppy (registered trademark)disk, a hard disk, an optical disk, a magneto-optical disk, a CompactDisk (CD)-ROM, a magnetic tape, a nonvolatile memory card, or a ROM canbe used. Further, the scope of each of the example embodiments includesan example that operates on Operating System (OS) to perform a processin cooperation with another software or a function of an add-in boardwithout being limited to an example that performs a process by anindividual program stored in the storage medium.

The service implemented by the function of each example embodimentdescribed above can be provided to the user in a form of Software as aService (SaaS).

Note that all the example embodiments described above are mere examplesof embodiment in implementing the present invention, and the technicalscope of the present invention should not be construed in a limitingsense by these example embodiments. That is, the present invention canbe implemented in various forms without departing from the technicalconcept thereof or the primary feature thereof.

The whole or part of the example embodiments disclosed above can bedescribed as, but not limited to, the following supplementary notes.

(Supplementary Note 1)

A colored contact lens comprising:

a lens; and

a colored region formed in the lens,

wherein at least a part of the colored region is arranged at a positionoverlapping an iris of a wearer when the colored contact lens is worn,and

wherein the colored region has infrared transparency.

(Supplementary Note 2)

The colored contact lens according to supplementary note 1, wherein atleast a part of a pattern of the iris is unable to be determined by avisible light but is able to be determined by an infrared ray when thecolored contact lens is worn.

(Supplementary Note 3)

The colored contact lens according to supplementary note 1 or 2, whereinthe colored region has transparency to a light whose wavelength islonger than 750 nm.

(Supplementary Note 4)

The colored contact lens according to any one of supplementary notes 1to 3, wherein the colored region has transparency to a light whosewavelength is longer than 750 nm and shorter than 1000 nm.

(Supplementary Note 5)

The colored contact lens according to any one of supplementary notes 1to 4, wherein the colored region has absorbability or reflectivity to alight whose wavelength is longer than or equal to 400 nm and shorterthan or equal to 750 nm.

(Supplementary Note 6)

The colored contact lens according to any one of supplementary notes 1to 5, wherein a transmittance of the colored region to a light whosewavelength is longer than 750 nm and shorter than 1000 nm is larger thana transmittance of the colored region to a light whose wavelength islonger than or equal to 400 nm and shorter than or equal to 750 nm.

(Supplementary Note 7)

The colored contact lens according to any one of supplementary notes 1to 6, wherein the colored region is arranged at a position that coversan outer circumference of the iris when the colored contact lens isworn.

(Supplementary Note 8)

The colored contact lens according to supplementary note 7, wherein thecolored region is arranged at a position that does not cover a pupil ofthe wearer when the colored contact lens is worn.

(Supplementary Note 9)

The colored contact lens according to any one of supplementary notes 1to 8,

wherein the colored region is formed of a coloring material havinginfrared transparency, and

wherein the coloring material is not contained in a surface of the lensbut contained inside the lens.

(Supplementary Note 10)

An iris recognition system comprising an infrared image acquisition unitthat captures an iris of a recognition subject wearing the coloredcontact lens according to any one of supplementary notes 1 to 9 by usinginfrared ray of a wavelength that transmits the colored region.

(Supplementary Note 11)

An iris recognition system comprising:

an infrared image acquisition unit that captures an iris of arecognition subject wearing a colored contact lens having a coloredregion by using an infrared ray having a wavelength that transmits thecolored region;

a visible light image acquisition unit that captures the iris by using avisible light;

a determination unit that determines whether or not the recognitionsubject is wearing the colored contact lens; and

a comparison unit that performs comparison on the iris,

wherein when the determination unit determines that the recognitionsubject is wearing the colored contact lens, the recognition unitperforms comparison by using an image acquired by an infrared ray, and

wherein when the determination unit determines that the recognitionsubject is not wearing the colored contact lens, the recognition unitperforms comparison by using an image acquired by a visible light or aninfrared ray.

(Supplementary Note 12)

A manufacturing method of a colored contact lens, the manufacturingmethod comprising:

forming a lens; and

forming a colored region in the lens,

wherein at least a part of the colored region is arranged at a positionoverlapping an iris of a wearer when the colored contact lens is worn,and

wherein the colored region has infrared transparency.

(Supplementary Note 13)

The manufacturing method of the colored contact lens according tosupplementary note 12,

wherein the colored region is formed of a coloring material havinginfrared transparency, and

wherein the coloring material is not contained in a surface of the lensbut contained inside the lens.

This application is based upon and claims the benefit of priority fromJapanese Patent Application No. 2017-224343, filed on Nov. 22, 2017, thedisclosure of which is incorporated herein in its entirety by reference.

REFERENCE SIGNS LIST

-   10 colored contact lens-   100 lens-   110 colored region-   120 transparent portion

1. A contact lens comprising: a lens; and a first region formed in thelens, wherein at least a part of the first region is arranged at aposition overlapping an iris of a wearer and is not arranged at aposition overlapping a pupil of the wearer when the contact lens isworn, and wherein the first region has transparency to a light having afirst wavelength and has absorbability or reflectivity to a light havinga second wavelength.
 2. The contact lens according to claim 1 furthercomprising a second region formed in the lens, wherein at least a partof the second region is arranged at a position overlapping the pupil ofthe wearer when the contact lens is worn, and wherein the second regionhas transparency to a light having the second wavelength.
 3. The contactlens according to claim 1, wherein at least a part of a pattern of theiris is unable to be determined by a light having the second wavelengthbut is able to be determined by a light having the first wavelength whenthe contact lens is worn.
 4. The contact lens according to claim 1,wherein the first wavelength is longer than 750 nm.
 5. The contact lensaccording to claim 1, wherein the first wavelength is longer than 750 nmand shorter than 1000 nm.
 6. The contact lens according to claim 1,wherein the second wavelength is longer than or equal to 400 nm andshorter than or equal to 750 nm.
 7. The contact lens according to claim1, wherein a transmittance of the first region to a light whosewavelength is longer than 750 nm and shorter than 1000 nm is larger thana transmittance of the first region to a light whose wavelength islonger than or equal to 400 nm and shorter than or equal to 750 nm. 8.The contact lens according to claim 1, wherein the first region isarranged at a position that covers an outer circumference of the iriswhen the contact lens is worn.
 9. The contact lens according to claim 1,wherein the first region is formed of a coloring material havinginfrared transparency, and wherein the coloring material is notcontained in a surface of the lens but contained inside the lens.
 10. Aniris recognition system comprising a first image acquisition unit thatcaptures an iris of a recognition subject wearing the contact lensaccording to claim 1 by using a light having the first wavelength. 11.An iris recognition system comprising: a first image acquisition unitthat captures an iris of a recognition subject wearing a contact lenshaving a first region by using a light having a first wavelength thattransmits the first region, wherein the first region has transparency toa light having the first wavelength and has absorbability orreflectivity to a light having a second wavelength; a second imageacquisition unit that captures the iris by using a light having thesecond wavelength; a determination unit that determines whether or notthe recognition subject is wearing the contact lens; and a comparisonunit that performs comparison on the iris, wherein when thedetermination unit determines that the recognition subject is wearingthe contact lens, the comparison unit performs comparison by using animage acquired by a light having the first wavelength, and wherein whenthe determination unit determines that the recognition subject is notwearing the contact lens, the comparison unit performs comparison byusing an image acquired by a light having the first wavelength or alight having the second wavelength.
 12. A manufacturing method of acontact lens, the manufacturing method comprising: forming a lens; andforming a first region in the lens, wherein at least a part of the firstregion is arranged at a position overlapping an iris of a wearer and isnot arranged at a position overlapping a pupil of the wearer when thecontact lens is worn, and wherein the first region has transparency to alight having a first wavelength and has absorbability or reflectivity toa light having a second wavelength.
 13. The manufacturing method of thecontact lens according to claim 12, wherein the first region is formedof a coloring material having infrared transparency, and wherein thecoloring material is not contained in a surface of the lens butcontained inside the lens.
 14. The contact lens according to claim 1,wherein the first region does not cover a pupil of the wearer when thecontact lens is worn.